1. Field of the Invention
This invention relates to particulate material comprising a binder, and a method for making same. When the particulate material further contains abrasive grits, it can be used in bonded abrasives, coated abrasives, and nonwoven abrasives.
2. Discussion of the Art
Conventional coated abrasive articles typically consist of a layer of abrasive grits adhered to a backing. Generally only a small fraction of the abrasive grits in this layer are actually utilized during the useful life of the coated abrasive article. A large proportion of the abrasive grits in this layer are wasted. Furthermore, the backing, one of the more expensive components of the coated abrasive article, must also be disposed of before it has worn out.
Many attempts have been made to distribute the abrasive grits on the backing in such a manner so that a higher percentage of abrasive grits are actually utilized, thereby extending the useful life of the coated abrasive article. By extending the life of the coated abrasive article, fewer belt or disc changes are required, thereby saving time and reducing labor costs. Merely depositing a thick layer of abrasive grits on the backing will not solve the problem, because grits lying below the topmost grits are not likely to be used.
Several methods whereby abrasive grits can be distributed in a coated abrasive article in such a way as to prolong the life of the article are known. One such way involves incorporating abrasive agglomerates in the coated abrasive article. Abrasive agglomerates consist of abrasive grits bonded together by means of a binder to form a mass. The use of abrasive agglomerates having random shapes and sizes makes it difficult to predictably control the quantity of abrasive grits that come into contact with the surface of a workpiece. For this reason, it would be desirable to have an economical way to prepare precisely shaped abrasive agglomerates.